I got a new MKS 1.4 controller board and it came with A4988 driver chips. But I can't figure out which way they install. I found something saying to match the printing on the back of the chip to that on the board. But I don't see anything that matches. Suggestions?

$\begingroup$You might be able to figure this out with a multimeter. The 1A/2A/1B/2B pins should have continuity to the connectors for the motors.$\endgroup$
– Tom van der ZandenJan 23 '17 at 8:16

$\begingroup$Thanks - I found a pin diagram last night that indicates the same.$\endgroup$
– CoAstroGeekJan 23 '17 at 13:01

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$\begingroup$In that case, consider writing an answer to your own question, so that the next person who finds this question via google actually finds an answer here.$\endgroup$
– Tom van der ZandenJan 23 '17 at 13:09

$\begingroup$Will do, as soon as I can confirm it.$\endgroup$
– CoAstroGeekJan 23 '17 at 15:59

3 Answers
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Note the two square pads for the GND, whereas the others are round. Now looking at the top side:

and note the position of the square GND pins/pads, in relation to the trim pot.

Now look at this hi-res photo of a populated MKS board

Again, looking at the position of the trim pots, one can see that the A4988 breakout boards need to be oriented such that the side with GND pins need to be nearest to the top of the board. That is to say the GND on the corner of the breakout board, needs to be pointing North East, as it were.